“Always Been You” was first previewed as a demo track in Shawn Mendes' 2020 documentary Shawn Mendes: In Wonder. The track was played again in the documentary during a studio session fleshing the idea out more.

When talking about “Always Been You,” Shawn said:

I wrote this in the green room the other day. No lyrics. […] I wanna write a song that’s like orchestra in heaven with massive drums and it goes [makes buzzing drum sound] and then really quiet, my vocal just goes ‘It’s always been you, it’s always been you.’